A LED lamp or LED light bulb is an electric light for use in light fixtures that produces light using light-emitting diode (LED). LED lamps have a lifespan and electrical efficiency which are several times greater than incandescent lamps, and are significantly more efficient than most fluorescent lamps, with some chips able to emit more than 300 lumens per watt. The LED lamp market is projected to grow by more than twelve-fold over the next decade, from $2 billion in the beginning of 2014 to $25 billion in 2023.
Contemporary bulbs typically used a single large LED or matrix of LEDs. Therefore, these bulbs typically produced only a 180-degree range of light. By the mid-2010s, LED filaments were being introduced into the market by several manufacturers. These designs used several LED filament light producers arranged in the same or similar pattern to that found in the wires of standard incandescent bulb.
The LED filament consists of multiple series-connected LEDs on a transparent substrate, referred to as Chip-On-Glass (COG). These transparent substrates are made of glass or sapphire materials. This transparency allows the emitted light to disperse evenly and uniformly without any interference. An even coating of yellow phosphor in a silicone resin binder material converts the blue light generated by the LEDs into white light.
Although LED filament bulbs produce omnidirectional light just as much as incandescent lights, LED filament bulbs generally reach lengths up to about eight inches. Moreover, LED filament bulbs have a relatively short life span of 15.000 to 28,000 hours.